| Date | May 2021 | Marks available | 1 | Reference code | 21M.1.HL:.tz0.29 |
| Level | Higher Level | Paper | Paper 1 | Time zone | time zone 0 |
| Command term | Question number | 29 | Adapted from | N/A |
Question
How are circulating hormone levels regulated?
I. Feedback loops
II. Signals from the nervous system
III. Chemical changes in the blood and other hormones
A. I and II only
B. I and III only
C. II and III only
D. I, II and III
Markscheme
D
Examiners report
Mid-difficulty question.
